High T-cell response to human cytomegalovirus induces chemokine-mediated endothelial cell damage

Human cytomegalovirus (CMV) infection has been linked to inflammatory diseases that involve vascular endothelial damage, including vascular disease and chronic transplant rejection. We previously reported that the host CD4(+) T-cell response to CMV antigen presented by endothelial cells can produce interferon-gamma and tumor necrosis factor-alpha at levels sufficient to drive induction of fractalkine, a key marker of inflammation, in endothelial cells. In this work, we report that donors with high frequencies of antigen-specific T cells to CMV (high responders) induce higher levels of activation-associated chemokines such as fractalkine, RANTES (regulated on activation, normal T cell expressed and secreted), and macrophage inflammatory protein-1beta, together with cell-adhesion markers in endothelial cells compared with donors with low levels of CMV-specific T cells (low responders). High-responder cultures had higher levels of leukocyte recruitment and adherence to the endothelial monolayers associated with progressive damage and loss of the endothelial cells. These processes that led to endothelial destruction only required viral antigen and did not require infectious virus. Our findings further support that CMV may represent one member of a class of persistent pathogens in which a high antigen-specific T-cell response defines an important risk factor for development of chronic inflammation and endothelial cell injury.